can anyone tell my the size of the posi unit in a 91 z28 5.0tpi,all I know is that it's a 10 bolt.also what advantages will I get if I change the gears to 3.73?

 

Its a 7.625" 10-bolt with 28 spline axles. You dont list if you have an automatic or a 5-speed, but if you have an automatic with 2.73 gears or a 5-speed (single cat) with 3.08 gears, you'll need to get gears for a 2-series carrier, and if you have a 5-speed (dual cats) with 3.42 gears, you'll need to get gears for a 3-series carrier. A search on this forum will tell you more info.

 

its a 700r4,so a 7.5 would fit?

 

7.5 and 7.62 are the same, or interchange